1) Field of the Invention
The present invention relates to a method of measuring a cumulative processing time for modules required in a process to be traced, by measuring a current time of a start point and an end point of each required module.
2) Description of the Related Art
The present intense competition for the development of new products has engineers and designers of new products working day and night, and an effective method of reducing the work load of the engineers and designers is the use of a CAD (Computer Aided Design) system.
Usually, the hardware of the CAD system includes a computer (a minicomputer or a microcomputer), an external memory device such as a magnetic disk or magnetic tape, an image scanner, a graphic display, a key board, a plotter, and a machining center and so on. For example, the designer can define only a three-dimensional structure by a wire-frame on the graphic display, and then inputs a color, light source or texture parameter to obtain a display of a variety of actual images of new products, by using this system.
The software of the CAD system, however, is modularized into functional units. Namely, the software of the CAD system includes, for example, following modules: a surface modelling module for constructing a three-dimensional structure in the computer; a drafting module for automatically drawing dimensional lines; a design simulation module for realizing a stereoscopic image on the display; an instant shading module for instantaneously adding shading and shadows to the three-dimensional structure displayed; a parametric graphic defining module for making up a family of devices from one base device, by inputting actual dimensions; a mechanism simulation module for simulating a movement of a movable device; a database management module for classifying and arranging design data; a plotter output module for plotting a designed device; and a numeric control module for operating a machining center to thereby manufacture a device; and so on.
Note, a number of different CAD systems are available, and the software of a CAD system that is popular among users is always in demand. Accordingly, the manufacturers of software for the CAD system are always trying to make their software more efficient and with more functions.
In this connection, if the manufactured software program for a CAD system including many modules does not satisfy the required performance criteria, it is difficult to find which module is unsatisfactory. Namely, in the prior art, it is difficult to determine which module is frequently called up and operated, and thus it is difficult to calculate the operating time of each module.